Autonomous fuel element washing device - for foreign body and deposit removal from PWR or BWR fuel element

摘要

An autonomous fuel element washing system, esp. for removing foreign bodies and deposits from the fuel elements of PWRs and BWRs is mounted or retrofitted in the sipping boxes already installed in the fuel element pond of the reactor. The washing device consists of a washing ring and a suction ring fitted between the compensator ring and the loading machine centring flange such that the sipping box length is not altered and the closure cover mechanism need not be modified. The washing ring has rows of exchangeable nozzles which are located above the fluid chamber and which are sepd. by partitions into four chambers directly connected by washing ring pipes to the connection lines. The suction ring has no peripheral partitions and is connected by stabilised suction line devices to the suction connection line which leads, via a disposable dirt filter in the pond, to a piston dosing pump installed outside the pond. Conventional system circuits are coupled to the washing connection lines. ADVANTAGE - The system provides reliable removal of foreign bodies and deposits by an alternating hydraulic washing and suction action.